Study: Spices might sub for pesticides

VANCOUVER, British Columbia, Aug. 18 (UPI) -- A Canadian study suggests some spices might be a good substitute for the use of pesticides in fighting insects that destroy organic food crops.

University of British Columbia researchers led by Professor Murray Isman said spices such as rosemary, thyme, clove and mint -- the so-called "essential oil pesticides" -- represent a relatively new class of natural insecticides that show promise as being environmentally friendly, posing less risk to human and animal health.

"We are exploring the potential use of natural pesticides based on plant essential oils commonly used in foods and beverages as flavorings," Isman said, noting they are generally a mixture of tiny amounts of two to four spices diluted in water. Some kill insects, while others repel them. "These products expand the limited arsenal of organic growers to combat pests. They're still only a small piece of the insecticide market, but they're growing and gaining momentum."

Unlike conventional pesticides, the spice-based pesticides do not require extensive regulatory approval. However, while they are less likely to evolve resistance, they tend to evaporate quickly and degrade rapidly in sunlight, Isman said. Researchers are now seeking ways of making the natural pesticides longer-lasting and more potent.

The study was presented Sunday in Washington during a meeting of the American Chemical Society.